I love Northern Indian cuisine, but am allergic to cumin. Can anyone suggest a substitute for cumin to use in making garam masala from Northern India?
There seem to be more than a few well known curries that use neither garam masala nor cumin - for example, Camellia Panjabi's "50 great curries of india" (an older vintage but good cookbook IMHO) lists a Rogan Josh and a Safed Murgh Korma meeting this constraint.
Also, "Nadan" style south indian beef curries seem to be commonly cumin-less, and they could fit well together with north indian dishes even while not north indian.
Also, while it is a different flavor, Ajowan (or even Thyme) can go great lengths at creating a "balanced" indian flavor profile where nothing seems missing (it is commonly used as one of defining spices in samosas).
My recommendation is that you simply omit the cumin. Garam Masala, depending on the recipe you follow, has 6-8 other spices in it. Chances are, if you just take out the cumin, you won't notice.
If you try the result and you feel that it's really missing something, then I'd suggest adding fennel seed, black mustard seed, or a second variety of dried chile pepper.
You can try replacing it with dill seeds. However, what exactly is it in cumin that causes your allergy? Find that out and avoid that whole class of spices/plants. I think cumin is from parsley family.
You can try using mustard seed powder instead of cumin and make your "garam' masala.
Also, read this to get more ideas/substitutes http://adventuresinspice.com/flavormap/flavormap.html#cumin
you should also read this thread: What is this fungus/lichen in my Garam Masala? (“Trifle”/truffle?)